[Clang][CodeGen] Do not set inbounds flag for struct GEP with null base pointers by dtcxzyw · Pull Request #130734 · llvm/llvm-project (original) (raw)
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Clang issues not falling into any other category
IR generation bugs: mangling, exceptions, etc.
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dtcxzyw added a commit that referenced this pull request
… type (#134221)
If CreateConstInBoundsGEP2_32 returns a constant null/gep, the cast to
GetElementPtrInst will fail.
This patch uses two static helpers
GEPOperator::accumulateConstantOffset/GetElementPtrInst::getIndexedType
to infer offset and result type instead of depending on the GEP result.
This patch is extracted from #130734.
llvm-sync bot pushed a commit to arm/arm-toolchain that referenced this pull request
… and result type (#134221)
If CreateConstInBoundsGEP2_32 returns a constant null/gep, the cast to
GetElementPtrInst will fail.
This patch uses two static helpers
GEPOperator::accumulateConstantOffset/GetElementPtrInst::getIndexedType
to infer offset and result type instead of depending on the GEP result.
This patch is extracted from llvm/llvm-project#130734.
dtcxzyw added a commit that referenced this pull request
This patch turns off inbounds/nuw flags for member accesses when
-fwrapv-pointer is set.
Closes #132449.
It is required by #130734.
llvm-sync bot pushed a commit to arm/arm-toolchain that referenced this pull request
AllinLeeYL pushed a commit to AllinLeeYL/llvm-project that referenced this pull request
dtcxzyw added a commit that referenced this pull request
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var-const pushed a commit to ldionne/llvm-project that referenced this pull request
var-const pushed a commit to ldionne/llvm-project that referenced this pull request
…se pointers (llvm#130734)
In the LLVM middle-end we want to fold gep inbounds null, idx -> null:
https://alive2.llvm.org/ce/z/5ZkPx-
This pattern is common in real-world programs
(dtcxzyw/llvm-opt-benchmark#55 (comment)).
Generally, it exists in some (actually) unreachable blocks, which is
introduced by JumpThreading.
However, some old-style offsetof macros are still widely used in real-world C/C++ code (e.g., hwloc/slurm/luajit). To avoid breaking existing code and inconvenience to downstream users, this patch removes the inbounds flag from the struct gep if the base pointer is null.
var-const pushed a commit to ldionne/llvm-project that referenced this pull request
dtcxzyw added a commit that referenced this pull request
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IanWood1 pushed a commit to IanWood1/llvm-project that referenced this pull request
IanWood1 pushed a commit to IanWood1/llvm-project that referenced this pull request